/*_############################################################################
  _## 
  _##  SNMP4J 2 - UnsignedInteger32.java  
  _## 
  _##  Copyright (C) 2003-2011  Frank Fock and Jochen Katz (SNMP4J.org)
  _##  
  _##  Licensed under the Apache License, Version 2.0 (the "License");
  _##  you may not use this file except in compliance with the License.
  _##  You may obtain a copy of the License at
  _##  
  _##      http://www.apache.org/licenses/LICENSE-2.0
  _##  
  _##  Unless required by applicable law or agreed to in writing, software
  _##  distributed under the License is distributed on an "AS IS" BASIS,
  _##  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  _##  See the License for the specific language governing permissions and
  _##  limitations under the License.
  _##  
  _##########################################################################*/
package org.snmp4j.smi;

import java.io.*;
import org.snmp4j.asn1.BER;
import org.snmp4j.asn1.BERInputStream;

/**
 * UnsignedInteger32 type is an SNMP type that represents unsigned 32bit
 * integer values (0 to 4294967295).
 *
 * @author Frank Fock
 * @version 1.8
 */
public class UnsignedInteger32 extends AbstractVariable implements AssignableFromLong, AssignableFromString {

    private static final long serialVersionUID = -2155365655395258383L;

    protected long value = 0;

    public UnsignedInteger32() {
    }

    /**
     * Creates an <code>UnsignedInteger32</code> from a <code>long</code> value.
     * @param value
     *    a <code>long</code> value which must not be greater 2^32-1 and not less
     *    zero.
     * @throws IllegalArgumentException
     *    if <code>value</code> &lt; 0 or &gt; 2^32-1.
     */
    public UnsignedInteger32(long value) {
        setValue(value);
    }

    /**
     * Creates an unsigned integer from a signed int value. Negative values
     * will become 2^31-1 through 2^32-1.
     * @param signedIntValue
     *    a signed int value.
     * @since 1.7
     */
    public UnsignedInteger32(int signedIntValue) {
        setValue(signedIntValue & 0xFFFFFFFFL);
    }

    /**
     * Creates an unsigned integer from a signed byte value. Negative values
     * will become 2^7-1 through 2^8-1.
     * @param signedByteValue
     *    a signed byte value.
     * @since 1.7
     */
    public UnsignedInteger32(byte signedByteValue) {
        setValue(signedByteValue & 0xFF);
    }

    public void encodeBER(OutputStream outputStream) throws java.io.IOException {
        BER.encodeUnsignedInteger(outputStream, BER.GAUGE, value);
    }

    public void decodeBER(BERInputStream inputStream) throws java.io.IOException {
        BER.MutableByte type = new BER.MutableByte();
        long newValue = BER.decodeUnsignedInteger(inputStream, type);
        if (type.getValue() != BER.GAUGE) {
            throw new IOException("Wrong type encountered when decoding Gauge: " + type.getValue());
        }
        setValue(newValue);
    }

    public int getSyntax() {
        return SMIConstants.SYNTAX_UNSIGNED_INTEGER32;
    }

    public int hashCode() {
        return (int) value;
    }

    public int getBERLength() {
        if (value < 0x80L) {
            return 3;
        } else if (value < 0x8000L) {
            return 4;
        } else if (value < 0x800000L) {
            return 5;
        } else if (value < 0x80000000L) {
            return 6;
        }
        return 7;
    }

    public boolean equals(Object o) {
        if (o instanceof UnsignedInteger32) {
            return (((UnsignedInteger32) o).value == value);
        }
        return false;
    }

    public int compareTo(Variable o) {
        long diff = (value - ((UnsignedInteger32) o).getValue());
        if (diff < 0) {
            return -1;
        } else if (diff > 0) {
            return 1;
        }
        return 0;
    }

    public String toString() {
        return Long.toString(value);
    }

    public final void setValue(String value) {
        setValue(Long.parseLong(value));
    }

    public void setValue(long value) {
        if ((value < 0) || (value > 4294967295L)) {
            throw new IllegalArgumentException("Argument must be an unsigned 32bit value");
        }
        this.value = value;
    }

    public long getValue() {
        return value;
    }

    public Object clone() {
        return new UnsignedInteger32(value);
    }

    public final int toInt() {
        return (int) getValue();
    }

    public final long toLong() {
        return getValue();
    }

    public OID toSubIndex(boolean impliedLength) {
        return new OID(new int[] { toInt() });
    }

    public void fromSubIndex(OID subIndex, boolean impliedLength) {
        setValue(subIndex.getUnsigned(0));
    }

}
